Now she faces her biggest challenge yet – making the Times paywalls work.

Hence her fall down this year's MediaGuardian 100 from eighth position in last year's list, despite her pivotal role in persuading the Murdochs – Jr and Sr – that the Tory leader was worthy of their support.

"Rebekah Brooks is the messenger between the Tory leader and the Murdochs," said our panel. "She will be the one going to Downing Street to visit Cameron. She is an ambassador and a brilliant networker."

She had previously spent six years editing the country's biggest-selling daily paper, the Sun, and three years in charge of the News of the World. She was succeeded at the Sun by her preferred candidate, her former deputy Dominic Mohan.